Dual output uninterruptible power supply

ABSTRACT

An uninterruptible power supply (UPS) includes a rectifier configured to receive alternating current (AC) power. The UPS further includes a first output connected to the rectifier through an inverter. The first output is configured to output an AC power supply. The UPS also includes a second output connected to the rectifier through a battery backup and a stepdown converter. The second output is configured to output a direct current (DC) power supply in response to a detected power anomaly condition, thereby providing extra redundancy that allows for increased power availability and uptime.

BACKGROUND

In certain environments, a number of computing devices operate togetherat a particular location to provide a service, such as data centers orserver farms providing services over the Internet. It is desirable tohave a constant source of power at such locations so that the computersand other devices operating at that location continue functioning.Providing a constant source of power, however, can be difficult becausepower providers occasionally experience power outages or other powerfailures occur. As such, a backup power supply to protect against such apower outage is beneficial.

Backup power can be provided by an uninterruptible power source oruninterruptible power supply (UPS). The UPS provides emergency power toa load (such as the computing devices) when the input power source ormain power fails. The UPS provides near-instantaneous protection frominput power interruptions, by supplying energy stored, for example, inbatteries.

In a standard Information Technology (IT) equipment rack in a datacenter, AC power goes into the UPS, which outputs AC to a powerdistribution unit (PDU) to be distributed to all the power supply units(PSUs) in the rack. In recent years, power supply arrangements have beenconfigured in a power shelf infrastructure. The power shelf is arackmount system used in data center racks designed to provide powerrectification, system management and power distribution. However,current power shelf architectures sometimes do provide power backupredundancy that ensures a long enough power supply during a powerfailure, which would be beneficial to ensure constant power (at leastfor a short time period), such as to critical IT equipment in the datacenter during the power failure.

SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

An uninterruptible power supply (UPS) comprises a rectifier configuredto receive alternating current (AC) power. The UPS further comprises afirst output connected to the rectifier through an inverter. The firstoutput is configured to output an AC power supply. The UPS alsocomprises a second output connected to the rectifier through a batterybackup and a stepdown converter. The second output is configured tooutput a direct current (DC) power supply in response to a detectedpower anomaly condition.

Many of the attendant features will be more readily appreciated as thesame becomes better understood by reference to the following detaileddescription considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present description will be better understood from the followingdetailed description read in light of the accompanying drawings,wherein:

FIG. 1 is a block diagram illustrating a system having a UPS accordingto an embodiment;

FIG. 2 is a schematic block diagram of a UPS according to an embodiment;

FIG. 3 is a block diagram illustrating a side view of an InternetTechnology (IT) rack according to an embodiment;

FIG. 4 is a block diagram illustrating a back view of the IT rack ofFIG. 3;

FIG. 5 illustrates multi-mode operation of a UPS according to anembodiment;

FIG. 6 is a flowchart of a process for providing a UPS according to anembodiment;

FIG. 7 is a flowchart of a process for providing power during poweranomaly conditions according to an embodiment; and

FIG. 8 is a block diagram of an example computing environment suitablefor implementing some of the various examples disclosed herein.

Corresponding reference characters indicate corresponding partsthroughout the drawings. In the figures, the systems are illustrated asschematic drawings. The drawings may not be to scale.

DETAILED DESCRIPTION

The systems and methods described herein are configured to provide adual output UPS that has extra redundancy. In one implementation, amulti-mode system UPS includes two outputs to accommodate differentpower outage conditions and can sustain a power outage for a time period(e.g., five minutes) to allow, for example, critical operations to beperformed before system shutdown, switchover, etc. The UPS is operablein different modes, including a high efficiency mode and doubleconversion mode (input instability),

In some examples, an alternating current/direct current (AC/DC) dualoutput UPS is configured for operation in a power shelf rack. In oneparticular implementation, redundancy is provided such that the systemdoes not rely solely on the power shelf to supply power (e.g., 12Vpower), but the UPS is also able to provide 12V power in the case ofpower anomalies (e.g., power outage to the power shelf). As a result,power availability/uptime is increased. Thus, an additional redundancyis thereby provided.

FIG. 1 illustrates an example system 100 implementing a rack-based UPSin accordance with one or more implementations. In one particularexample, a multi-mode UPS includes a first output and a second output.The multi-mode UPS may be configured for operation in a data center,such as a 17 KW UPS operable in a high efficiency mode and doubleconversion mode (input instability), as well as configured to sustain apower outage for a period of time.

More particularly, and continuing with the data center example, the datacenter includes multiple computing devices and optionally othernetworking devices that are located within a device rack. AC power isprovided to the data center from an external power source, and also froma backup generator in the event of a loss of power from the externalpower source. Additionally, each device rack has a rack power unit thatreceives the AC power and converts the AC power to DC power, which inturn is provided to the devices located within that device rack. Eachrack power unit also includes one or more batteries or battery packsthat provide power to the devices within that rack during a time periodbetween the loss of power from the external AC power source and, forexample, the backup generator becoming operational and providing ACpower to the data center. Each rack power unit can also provideadditional functionality. For example, the UPS is operable to output theAC output to the power shelf while switching off the second output. Inthe case of a power anomaly condition, the second output provides asource of DC power to a bus bar that can be current shared with thepower shelf output or operate alone as discussed herein.

With particular reference to the configuration illustrated in FIG. 1,the system 100 includes a data center 102, a backup generator 104, andexternal AC power 106 received from an external power source. The datacenter 102 includes one or more (n) device racks 110(1), . . . , 110(n),each including one or more devices 112 and a rack power unit 114. Thedevice racks 110 are also referred to herein as racks. It should benoted that although reference is made herein to device racks, thedevices 112 and power units 114 can alternatively be grouped into othercontainers, mounting units, or other grouping configurations. In suchconfigurations, the rack-based UPS techniques discussed herein can beimplemented based on such alternate groupings rather than based on arack.

The data center 102 operates to provide one or more services to variouscomputing devices. The computing devices can be located in closephysical proximity to the data center 102, and/or located across a widegeographic range (e.g., throughout a country or throughout the world).The data center 102 communicates with the computing devices via avariety of different networks, including the Internet, a local areanetwork (LAN), a cellular or other phone network, an intranet, otherpublic and/or proprietary networks, combinations thereof, and so forth.The data center 102 can be accessed by a variety of different types ofcomputing devices, such as a desktop computer, a laptop computer, amobile station, an entertainment appliance, a television, a set-top boxcommunicatively coupled to a display device, a cellular or otherwireless phone, a game console, an automotive computer, and so forth.

The data center 102 can provide one or more of a variety of differentservices to computing devices. In one example, the data center 102provides one or more of a social networking service, an email service, asearch service, an information resource/storage service, a messagingservice, an image and/or video sharing service, a gaming or otherentertainment service, and so forth. The one or more services providedby the data center 102 can be publicly available or alternatively accessto one or more of the services can be restricted to particular users(e.g., those having a valid account as verified by a service of datacenter 102).

In the system 100, external AC power 106 is power received from one ormore external power sources, such as a power station managed by a powerutility company. The external AC power 106 is, for example, single-phaseor 3-phase power. An interruption in external AC power 106 (alsoreferred to as a power outage or power failure) can occur, and is asituation where the expected external AC power 106 is not received bythe data center 102. A variety of causes exist for such an interruption,such as a failure at a power station that provides the power 106, afailure in a power transmission line between the power station and thedata center 102, among others. In some examples, the interruption canoccur as a result in a failure in a component of the system 100.

In the illustrated example, the backup generator 104 is a powergenerator that operates as a backup source of AC power in the event ofan interruption in the external AC power 106. The backup generator 104can be, for example, a diesel-powered or gas-powered generator. Althougha single backup generator 104 is illustrated in the system 100,optionally multiple backup generators 104 (e.g., each responsible forproviding AC power to one or more racks 110) can be included in system100. The backup generator 104 can provide, for example, single-phase or3-phase AC power, typically providing the same single-phase or 3-phasepower as the external AC power 106. Alternatively, the backup generator104 provides DC power rather than AC power.

The backup generator 104 in some examples is located in close physicalproximity to the data center 102. In one example, a controller in thebackup generator 104, or alternatively in another component or device,detects an interruption in the external AC power 106. In response to thedetected interruption in the external AC power 106, the backup generator104 is powered on and begins generating AC power to provide to the datacenter 102. Typically, there is a time period between the interruptionin the external AC power 106 and the backup generator 104 generatingsufficient AC power to power the data center 102 (at which point thebackup generator 104 is referred to as being online). This time periodcan vary based on one or more of the manner in which the interruption ofpower is detected, the power used by the data center 102, and theparticular backup generator 104. The rack power units 114 within theindividual racks of data center 102 provide power to the devices 112 inthe device racks 110 during this time period, as discussed in moredetail below.

Multiple devices 112 in the data center 102 operate to provide thefunctionality of the one or more services provided by the data center102. A variety of different types of devices can be included. Thedevices 112 include one or more server computers, such as rack serversor blade servers in one example. The devices 112 include one or moreother components, such as a networking component (e.g., a gateway, arouter, a switch), a data storage component (e.g., one or more magneticdisk drives), a cooling component (e.g., a fan), and so forth, in someexamples.

The devices 112 are located within the racks 110 of the data center 102.The rack 110 is a physical structure or housing into which multiplechassis can be inserted, mounted, or otherwise placed. The rack 110includes different physical locations where a chassis of a particularsize (referred to as a rack unit or RU) can be placed. Different typesof racks 110 can hold different numbers of chassis. In some examples,the rack 110 is configured to hold 50 chassis, 90 chassis, and so forth.The chassis in turn can house a variety of different components, such asthe device 112 or the rack power unit 114. Each rack 110 includes one ormore data buses, one or more control buses, and one or more power busesthat allow data and control information to be communicated to and fromthe devices 112, and allow power to be communicated to devices 112.

It should be noted that the rack power unit 114 can take differentconfigurations. In one example, the rack power unit 114 is configured ina power shelf configuration (as described in more detail herein inconnection with FIGS. 3 and 4) that allows for hot-swap insertion toallow power module exchange under live power operation. However, thepresent disclosure can be implemented in different configurations. Forexample, the rack power unit 114 can be configured such that AC power isprovided to a power distribution unit (PDU) that is then distributed toone or more power supply units (PSUs) in the rack 110.

In one example, each rack 110 includes one or more of the rack powerunits 114. Each rack power unit 114 receives AC power, which can be theexternal AC power 106 or AC power from the backup generator 104. Eachrack power unit 114 converts the received AC power into DC power, andprovides the DC power to the devices 112 within the same rack as thatrack power unit. For example, the rack power unit 114(1) provides DCpower to devices 112(1) in rack 110(1), but does not provide DC power todevices 112(n) in other racks (n). Additionally, although each rack 110is illustrated in FIG. 1 as including one rack power unit 114,alternatively a rack 110 can include two or more rack power units 114that each provide DC power to devices within the same rack as the two ormore rack power units.

Although the rack power units 114 are illustrated as receiving AC power,in other examples, the rack power units 114 receive a DC power input. Insuch examples, rather than (or in addition to) converting received ACpower into DC power, the rack power units convert received DC power to adesired voltage (e.g., as desired for a DC power bus within the rack110).

Each rack power unit 114 also includes one or more batteries or batterypacks and operates as a UPS for devices 112 in the same rack as the rackpower unit 114. In the event of an interruption in AC power received bythe rack power unit 114, the rack power unit 114 draws power from theone or more battery packs to provide to the devices 112. Thus, ifexternal AC power 106 is interrupted, the rack power unit 114 drawspower from the one or more battery packs to provide power to the devices112 until, for example, the backup generator 104 provides AC power tothe rack power unit 114.

FIG. 2 is a block diagram illustrating an example UPS 200 in accordancewith one example. The UPS 200 is an example of or can be embodied as therack power unit 114 of FIG. 1. The UPS 200 receives AC power 202, whichcan be from a variety of sources, such as a power station, a backupgenerator, and so forth. Although illustrated as AC power, the power 202can alternatively be DC power (e.g., from a backup generator providingDC power). As discussed herein, situations can arise where there is aninterruption in the AC power 202 from one source (e.g., a powerstation), followed by a time period until the AC power 202 is providedby another source (e.g., a backup generator).

The UPS 200 includes one or more battery backups 204. The number ofbattery backups 204 in the UPS 200 can vary. For example, multiplebattery backups 204 can be included in the UPS 200 for redundancy (e.g.,in the event of a failure of one of the battery backups 204). In theillustrated example, a single battery backups 204 is shown and is alithium-ion battery. However, different types of batteries can be used,such as sealed lead-acid batteries.

The UPS 200 includes an AC/DC converter, which is configured as arectifier/charger 206 in the illustrated example. In operation, therectifier/charger 206 converts AC power, which periodically changesdirection, to DC power, which flows in only one direction. The output ofthe rectifier/charger 206 is connected to the battery backup 204 andconverts the AC power 202 to DC power to charge the battery backup 204in some examples. The output of the battery backup 204 is also connectedto an inverter 208, which is configured as a power inverter is someexamples. The inverter 208 converts the DC power from therectifier/charger 206 back to AC power, which is then provided to afirst output 210. That is, a normal flow double conversion power path isdefined from the AC power 202 to the first output 210. Thus, the firstoutput 210 supplies AC power, such as to AC input IT equipment 212.However, as should be appreciated, the first output 210 can provide ACpower to any device capable of being powered by AC power.

The UPS 200 also includes a power path to a second output 214 thatsupplies DC power as an output. More particularly, the output of thebattery backup 204 is connected to stepdown converter 216 (also referredto as a buck converter). In the illustrated example, the stepdownconverter 216 converts the power supplied from the battery backup 204 toa defined lower level, which in this example is 12V. The stepdownconverter 216 is a DC-to-DC power converter that steps down voltage(while stepping up current) from the input to the output thereof, in oneexample. In operation, this power path provides a stepped down DC powersupply to the second output 214, which can be used to provide DC powerto DC devices. In the illustrated example, the second output 214 isconnected to a DC distribution bus bar 218, which provides DC power tovarious devices in the power rack, such as the rack 110 (shown in FIG.1). It should be noted that in the illustrated example, the output ofthe AC input IT equipment 212 is also connected to the DC distributionbar 218.

Thus, in the illustrated configuration, received AC power 202 isconverted to DC power, and the DC power is output from the second output214, such that this power is provided to the devices in the same rack.It should be noted that the DC power can be any of a variety ofdifferent voltages, such as 12 volts, 24 volts, 48 volts, etc. and isprovided to the devices in the same rack via the DC distribution bar218. That is, each device in the same rack is coupled to the DCdistribution bar 218. As such, rather than converting received AC powerto DC power, each device in the rack receives DC power via the DCdistribution bar 218.

It should be noted that the various components of the UPS 200 can bedifferently configured, such as based on the particular application,power requirements, etc. For example, the particular configuration ofthe battery backup 204, the rectifier/charger 206, the inverter 208, andthe stepdown converter 216 can be varied to meet the requirements for aparticular application.

In operation, the UPS 200 is thereby configured as a dual output powersupply, namely having the first output 210 and the second output 214.The first output 210 of the dual output power supply is configured toprovide AC output power that is powered through the rectifier/charger206 (and to the battery backup 204) and then through the inverter 208.Additionally, the second output 214 of the dual output power supply isconfigured to provide DC output power through the rectifier/charger 206,to the power supply 204, and then to the stepdown converter 216. Thus,dual output UPS power that includes switchable AC output power and DCpower provides extra redundancy in providing continuous power, includingincreased power availability and uptime.

In a normal operating state or condition, the UPS 200 is configured tooutput the AC output from the first output 210 to, for example the powershelf, while switching off the second output 214. In the case of a poweranomaly situation, the second output 214 is configured to source DCpower to the DC distribution bar 218 (configured as a bus bar) that iscurrent shared with the power shelf output in one example, or notcurrent shared and provides power alone in another example.

When input AC power instability occurs (e.g., detected by a powerdetection device), the power shelf operates in the double conversionmode (AC-to-DC-to-AC conversions) as discussed herein and is ready tosource from the battery backup 204. In a situation wherein the powershelf fails, and power is needed for the AC input IT equipment 212 inthe rack, the UPS 200 switches on (activates) the second output 214 andsources 12V DC power from the second output 214 until the power supply214 is depleted or necessary shut down operations are completed (e.g., anon-volatile dual in-line memory (NVDIMM) module or other random-accessmemory save completes).

In a situation where the rack, such as the AC input IT equipment 212, isdrawing more power than specified by the power cord for the rack (e.g.,exceeding the rated power of the power cord), the UPS 200 enables a peakshaving mode to help with the output load. In this mode of operation,the second output 214 current shares with the 12V output of the powershelf.

The UPS 200 also includes a static switch 220 and a bypass switch 222 insome examples. These switches are configured to select different modesof operation. For example, the static switch 220 (e.g., a semiconductorswitch) allows current flow therethrough in a normal power flow (highefficiency) mode of operation, and also prevents backflow of current. Inthis mode of operation, the AC power 202 is connected to the firstoutput 210. The bypass switch 222 is switchable to select a bypass modeof operation, such as when performing maintenance operations on the UPS200. That is, in the bypass mode, the power conversion components arebypassed.

It should be noted that the battery backup 204 in some examples is aplurality of battery packs that provide DC power to devices in the samerack via the DC distribution bar 218. In the rack-based UPS 200discussed herein, the battery packs are placed in the same rack as (andthus in close physical proximity to) the devices being powered by thebattery packs. This close physical proximity reduces (relative toenvironments in which the battery packs are further from the devicesbeing powered) losses that can be incurred as power is transferred tothe devices.

Furthermore, because power is distributed within the rack via the DCdistribution bar 218, conversions between AC and DC power need not beperformed when providing power from battery packs to the devices in therack. Rather, the power is provided more efficiently because powerlosses that can be incurred when converting between AC and DC power arenot experienced when providing power from the battery packs to thedevices in the rack. No additional conversions between AC and DC powerneed be performed for the sole benefit of battery packs. That is, thebattery packs are situated to receive DC power after the received ACpower has been converted.

In one example, a rack-based uninterruptible power source is implementedusing a single chassis, with the components included in that singlechassis. Alternatively, one or more of the components can be implementedacross multiple chassis, such as various components being implemented inone or more chassis. In some examples, the DC distribution bar 218 isconfigured as a power bus having multiple ports that are coupled to oneor more computing devices powered by the UPS 200 (e.g., the DCdistribution bar 218 can have multiple receptacles that are physicallyplugged into by the devices, or can have multiple cords and plugs thatare plugged into receptacles of the devices). In one example, a powersupply controller (e.g., the PDU) can manage the ports individually,allowing DC power to be turned on or turned off to a particular deviceas desired or needed and controlled by the power supply controller. Thepower supply controller can also monitor the power consumed at the powerport, and can use the information obtained from this monitoring indifferent manners, such as determining an average power usage of thedevice (and thus of the rack), peak power usage of the device (and thusof the rack), and so forth.

One example of a rack 300 is shown in FIGS. 3 and 4. The rack 300includes the UPS 200 and a power shelf (Pshelf) 302, which areconfigured to operate as described in more detail herein. That is, theUPS 200 is configured to provide extra redundancy in supplying power,such as to supply 12V power in case of power failure to the rack 300. Asa result, power availability and uptime during a power failure event isextended.

In the illustrated example, the rack 300 is connected to two separatepower supply lines 304 and 306 (Feed A and Feed B). In one particularimplementation, the power supply line 304 is connected to and providespower from an external power source to the UPS 200 and the power supplyline 306 is connected to and provides power from an external powersource to the power shelf 302. As such, the rack 300 is protected from asingle point of power failure. It should be noted that the UPS 200 andpower shelf 302 also include additional components, such as fans 308 and310 to cool these devices during operation.

As should be appreciated, the second output 214 (shown in FIG. 2) isconnected to the DC distribution bus bar 218. It should also beappreciated that the rack 300, in some examples, includes a detectiondevice that allows for the detection of output (e.g., droop output ofthe power shelf 302). This allows for a determination of a power supplyfailure condition or other power anomaly condition. In some examples, amanual activation element (e.g., button or switch) is provided to allowfor switching between the different modes of operation discussed herein.

Thus, the present disclosure provides, for example, the UPS 200 havingextra redundancy to critical IT equipment in the data center by usingdual outputs. For example, in the event of failure of the power shelf302, the UPS 200 activates the second output 214 and sources 12V powertherefrom. Additionally, when rack equipment draws more power than amaximum rating, the UPS 200 is configured such that the second output214 current shares with the 12V output of the power shelf 302. As such,the dual output UPS 200 provides redundancy in the rack 300 with thepower shelf 302 during different anomaly or failure events, such as:

1. During input failure, the power shelf 302 runs on a double conversionmode and source power is provided from battery backup, such as thebattery backup 204 in the UPS 200.

2. During power shelf failure, the UPS 200 activates the second output214 to power, for example, IT equipment in the rack 300.

3. When the rack equipment is drawing excess power or more power than arated level, the second output 214 of the UPS 200 current shares withthe 12V power output of the power shelf 302.

Various examples provide dual output UPS, such as the UPS 200 that isconfigured for multi-mode operation 500 as illustrated in FIG. 5. Asdiscussed herein, the UPS 200 provides different sources of powerdepending on the particular operating condition (e.g., normal operationor anomaly operation) by operating in different modes 502. It should beappreciated that while FIG. 5 illustrates a plurality of defined modes502, additional, fewer, or different modes of operation arecontemplated.

In the illustrated example, four modes of operation are possible:

1. High efficiency mode of operation.

2. Double conversion mode of operation.

3. Second output backup power mode of operation (i.e., power output fromthe second output 214).

4. Peak shaving mode of operation.

These modes of operation are discussed in more detail herein and arepossible as a result of the dual outputs of the UPS 200. The modes ofoperation allow for continuous power to be supplied during power anomalyconditions. As should be appreciated, at some point after the poweroutage occurs, providing of AC power resumes (whether from the externalpower source or from a backup generator). It should be noted that thepoint at which the power anomaly condition occurs (e.g., power failure)or the point at which AC power resumes (and thus the UPS ceases toprovide power) can be identified in a variety of manners in the powerfailure detection technology area.

It also should be appreciated that the output from various examples isuseful for managing power supplied to a system 800, which is describedin more detail in relation to FIG. 8.

FIG. 6 is a flowchart illustrating exemplary operations involved in amethod 600 for providing a UPS in accordance with various examples. Byproviding the UPS, power availability and uptime during a power anomalycondition can be increased. The operations illustrated in the flowchartdescribed herein can be performed in a different order than is shown,can include additional or fewer steps and can be modified as desired orneeded. Additionally, one or more operations can be performedsimultaneously, concurrently or sequentially.

More particularly, and with reference also to FIGS. 1-5, the method 600includes configuring a first output to output an AC power supply from anAC power source at 602. For example, as described herein, the UPS 200 isconfigured to output AC power at the first output 210. As such, duringnormal power conditions, the first output 210 provides AC power, forexample, to AC input IT equipment.

The method 600 also includes configuring a second output to output a DCpower supply from the AC power source at 604. For example, as describedherein, the UPS is configured to output DC power at the second output214. As such, during power anomaly conditions, the second output 214provides power or current shares power to, for example, DC devices orcomponents in a rack.

More particularly, at 604, the first and second outputs are operable inthe UPS 200 such that the second output is activated during a poweranomaly condition to (i) during a power failure, provide power from abattery backup unit or (ii) during an excess power condition, powershare with the power supply unit. Thus, additional redundancy isprovided by the method 600.

FIG. 7 is a flowchart illustrating exemplary operations involved in amethod 700 for providing power during power anomaly conditions inaccordance with various examples. By providing the power during theseconditions, critical devices can, for example, be properly shut down byproviding additional power for a time period after a power failure in arack.

More particularly, and with reference also to FIGS. 1-6, the method 700includes identifying a power anomaly condition at 702. For example, asdescribed herein, the power anomaly conditions can include, but are notlimited to, an input AC power instability, a power shelf failure, orequipment drawing an excess amount of power, among others. The poweranomaly condition is detected in some examples by measuring electricalvoltage or current, or other electrical characteristics at the input oroutput of one or more components in the rack, or at the input of therack.

The method 700 also includes activating a second output of a dual outputUPS at 704. For example, when the power anomaly condition is detected,and in response thereto, a DC output of the UPS (e.g., the second output214 of the UPS 200) is activated (e.g., an AC output of the UPS is nolonger providing power). For example, the second output is activated andallows 12V DC power to be provided to IT equipment in the rack until thebattery backup is depleted or shut down operations are completed by theIT equipment.

The method 700 further includes outputting power from the second outputat 706. For example, the DC output of the UPS outputs DC power to powerdevices within the rack when a power failure is detected or power shareswith a power supply unit of the rack during excess power times.

It should be noted that some examples are configured as an add-on ormodification kit to a multi-mode system UPS. That is, an existing UPS ismodifiable according to the various examples described herein, includingto perform the methods 600 and 700.

Thus, various examples provide a dual output UPS with additionaloperating modes and redundancy to facilitate providing power toequipment during power anomaly conditions.

Additional Examples

Some aspects and examples disclosed herein are directed to anuninterruptible power supply (UPS) comprising:

-   -   a rectifier configured to receive alternating current (AC)        power;    -   a first output connected to the rectifier through an inverter,        the first output configured to output an AC power supply; and    -   a second output connected to the rectifier through a battery        backup and a stepdown converter, the second output configured to        output a direct current (DC) power supply in response to a        detected power anomaly condition.

Additional aspects and examples disclosed herein are directed to a dualoutput uninterruptible power supply (UPS) comprising:

-   -   a first output;    -   a second output;    -   an alternating current (AC)/direct current (DC) converter        configured to convert input AC power to a DC power supplied to a        battery backup;    -   an inverter configured to convert the DC power to AC power to        output at the first output; and    -   a stepdown converter configured to step down the DC power to        output at the second output.

Additional aspects and examples disclosed herein are directed to amethod for providing an uninterruptible power supply (UPS), the methodcomprising:

-   -   configuring a first output of the UPS to output an AC power        supply from an AC power source; and    -   configuring a second output of the UPS to output a DC power        supply from an AC power source, the first and second outputs        being selectively operable in the UPS and the second output        activated during a power anomaly condition to (i) output power        during the power anomaly condition that is provided by a power        supply unit during normal operation or (ii) power share with a        power supply unit.

Alternatively, or in addition to the other examples described herein,examples include any combination of the following:

-   -   wherein the power anomaly condition comprises one of a power        failure or an excess power condition.    -   wherein the battery backup is connected between the rectifier        and the inverter.    -   wherein the UPS is coupled within a rack and further comprising        a power supply unit coupled within the rack, wherein the first        output is connected to AC powered equipment in the rack and the        second output is connected to a DC distribution bus bar, and the        DC power supply is sourced to the DC distribution bus bar as a        current shared power source with an output of the power supply        unit during the power anomaly condition.    -   further comprising a first power supply line connected to the        UPS and a second power supply line connected to the power supply        unit.    -   wherein the first output is configured to operate in a high        efficiency mode or a double conversion mode.    -   wherein the second output is activated in response to a power        anomaly condition.    -   wherein the second output is in an active state until one or        more shut down operations of connected devices having        random-access memory are completed.    -   wherein the first output is configured to operate in modes of        operation that are different than modes of operation of the        second output.    -   wherein the first and second output are configured for        selectable operation in a plurality of operating modes        comprising a high efficiency mode of operation, a double        conversion mode of operation, a second output backup power mode        of operation, and a peak shaving mode of operation.    -   configuring the first and second outputs to selectively operate        in a plurality of operating modes comprising a high efficiency        mode of operation, a double conversion mode of operation, a        second output backup power mode of operation, and a peak shaving        mode of operation.    -   configuring an alternating current (AC)/direct current (DC)        converter to convert the AC power source to a DC power supplied        to a battery backup.    -   configuring a stepdown converter to step down a voltage output        of the battery backup.    -   configuring the first and second outputs for operation at a same        time.

Example Operating Environment

FIG. 8 is a block diagram of an example system 800 implementing aspectsdisclosed herein, and is designated generally as a system 800. Thesystem 800 is but one example of a suitable computing environment and isnot intended to suggest any limitation as to the scope of use orfunctionality of the examples disclosed herein. Neither should thesystem 800 be interpreted as having any dependency or requirementrelating to any one or combination of components/modules illustrated.The examples disclosed herein may be described in the general context ofcomputer code or machine-useable instructions, includingcomputer-executable instructions such as program components, beingexecuted by a computer or other machine, such as a personal dataassistant or other handheld device. Generally, program componentsincluding routines, programs, objects, components, data structures, andthe like, refer to code that performs particular tasks, or implementparticular abstract data types. The discloses examples may be practicedin a variety of system configurations, including personal computers,laptops, smart phones, mobile tablets, hand-held devices, consumerelectronics, specialty computing devices, etc. The disclosed examplesmay also be practiced in distributed computing environments when tasksare performed by remote-processing devices that are linked through acommunications network.

The system 800 includes a bus 810 that directly or indirectly couplesthe following devices: a computer-storage memory 812, one or moreprocessors 814, one or more presentation components 816, input/output(I/O) ports 818, I/O components 820, a power supply 822 (that includesthe UPS 200), and a network component 824. While the system 800 isdepicted as a seemingly single device, multiple systems 800 can worktogether and share the depicted device resources. For instance, thecomputer-storage memory 812 can be distributed across multiple devices,processor(s) 814 may provide housed on different devices, and so on.

The bus 810 represents one or more busses (such as an address bus, databus, or a combination thereof). Although the various blocks of FIG. 8are shown with lines for the sake of clarity, in reality, delineatingvarious components is not so clear, and metaphorically, the lines wouldmore accurately be grey and fuzzy. For example, a presentation componentsuch as a display device can be considered to be an I/O component. Also,processors have memory and FIG. 8 is merely illustrative of an exemplarycomputing device that can be used in connection with one or moredisclosed examples. Distinction is not made between such categories as“workstation,” “server,” “laptop,” “hand-held device,” etc., as all arecontemplated within the scope of FIG. 8 and the references herein to a“system”. The computer-storage memory 812 may take the form of thecomputer-storage media references below and operatively provide storageof computer-readable instructions, data structures, program modules andother data for the system 800. For example, the computer-storage memory812 can store an operating system, a universal application platform, orother program modules and program data. The computer-storage memory 812can be used to store and access instructions configured to carry out thevarious operations disclosed herein.

As mentioned below, the computer-storage memory 812 may includecomputer-storage media in the form of volatile and/or nonvolatilememory, removable or non-removable memory, data disks in virtualenvironments, or a combination thereof. And the computer-storage memory812 may include any quantity of memory associated with or accessible bythe computing device 800. The memory 812 may be internal to thecomputing device 800 (as shown in FIG. 8), external to the computingdevice 800 (not shown), or both (not shown). Examples of the memory 812in include, without limitation, random access memory (RAM); read onlymemory (ROM); electronically erasable programmable read only memory(EEPROM); flash memory or other memory technologies; CD-ROM, digitalversatile disks (DVDs) or other optical or holographic media; magneticcassettes, magnetic tape, magnetic disk storage or other magneticstorage devices; memory wired into an analog computing device; or anyother medium for encoding desired information and for access by thecomputing device 800. Additionally, or alternatively, thecomputer-storage memory 812 may be distributed across multiple computingdevices 800, e.g., in a virtualized environment in which instructionprocessing is carried out on multiple devices 800. For the purposes ofthis disclosure, “computer storage media,” “computer-storage memory,”“memory,” and “memory devices” are synonymous terms for thecomputer-storage memory 812, and none of these terms include carrierwaves or propagating signaling.

Therefore, for example, a computer storage medium should not beinterpreted to be a propagating signal per se. Propagated signals per seare not examples of computer storage media. Although the computerstorage medium (the memory 812) is shown within the system 800, it willbe appreciated by a person skilled in the art, that the storage can bedistributed or located remotely and accessed via a network or othercommunication link (e.g. using a communication interface).

The processor(s) 814 may include any quantity of processing units thatread data from various entities, such as the memory 812 or I/Ocomponents 820. Specifically, the processor(s) 814 are programmed toexecute computer-executable instructions for implementing aspects of thedisclosure. The instructions may be performed by the processor, bymultiple processors within the computing device 800, or by a processorexternal to the client computing device 800. In some examples, theprocessor(s) 814 are programmed to execute instructions such as thoseillustrated in the flow charts discussed below and depicted in theaccompanying drawings. Moreover, in some examples, the processor(s) 814represent an implementation of analog techniques to perform theoperations described herein. For example, the operations may beperformed by an analog client computing device 800 and/or a digitalclient computing device 800. Presentation component(s) 816 present dataindications to a user or other device. Exemplary presentation componentsinclude a display device, speaker, printing component, vibratingcomponent, etc. One skilled in the art will understand and appreciatethat computer data may be presented in a number of ways, such asvisually in a graphical user interface (GUI), audibly through speakers,wirelessly between computing devices 800, across a wired connection, orin other ways. Ports 818 allow computing device 800 to be logicallycoupled to other devices including I/O components 820, some of which maybe built in. Examples I/O components 820 include, for example butwithout limitation, a microphone, joystick, game pad, satellite dish,scanner, printer, wireless device, etc.

The system 800 may operate in a networked environment via the networkcomponent 824 using logical connections to one or more remote computers.In some examples, the network component 824 includes a network interfacecard and/or computer-executable instructions (e.g., a driver) foroperating the network interface card. Communication between thecomputing device 800 and other devices may occur using any protocol ormechanism over any wired or wireless connection. In some examples, thenetwork component 824 is operable to communicate data over public,private, or hybrid (public and private) using a transfer protocol,between devices wirelessly using short range communication technologies(e.g., near-field communication (NFC), Bluetooth™ brandedcommunications, or the like), or a combination thereof. For example,network component 824 communicates over a communication link 826 with anetwork 828.

Although described in connection with an example system 800, examples ofthe disclosure are capable of implementation with numerous othergeneral-purpose or special-purpose computing system environments,configurations, or devices. Examples of well-known computing systems,environments, and/or configurations that may be suitable for use withaspects of the disclosure include, but are not limited to, smart phones,mobile tablets, mobile computing devices, personal computers, servercomputers, hand-held or laptop devices, multiprocessor systems, gamingconsoles, microprocessor-based systems, set top boxes, programmableconsumer electronics, mobile telephones, mobile computing and/orcommunication devices in wearable or accessory form factors (e.g.,watches, glasses, headsets, or earphones), network PCs, minicomputers,mainframe computers, distributed computing environments that include anyof the above systems or devices, VR devices, holographic device, and thelike. Such systems or devices may accept input from the user in any way,including from input devices such as a keyboard or pointing device, viagesture input, proximity input (such as by hovering), and/or via voiceinput.

Examples of the disclosure may be described in the general context ofcomputer-executable instructions, such as program modules, executed byone or more computers or other devices in software, firmware, hardware,or a combination thereof. The computer-executable instructions may beorganized into one or more computer-executable components or modules.Generally, program modules include, but are not limited to, routines,programs, objects, components, and data structures that performparticular tasks or implement particular abstract data types. Aspects ofthe disclosure may be implemented with any number and organization ofsuch components or modules. For example, aspects of the disclosure arenot limited to the specific computer-executable instructions or thespecific components or modules illustrated in the figures and describedherein. Other examples of the disclosure may include differentcomputer-executable instructions or components having more or lessfunctionality than illustrated and described herein. In examplesinvolving a general-purpose computer, aspects of the disclosuretransform the general-purpose computer into a special-purpose computingdevice when configured to execute the instructions described herein.

By way of example and not limitation, computer readable media comprisecomputer storage media and communication media. Computer storage mediainclude volatile and nonvolatile, removable and non-removable memoryimplemented in any method or technology for storage of information suchas computer readable instructions, data structures, program modules, orthe like. Computer storage media are tangible and mutually exclusive tocommunication media. Computer storage media are implemented in hardwareand exclude carrier waves and propagated signals. Computer storage mediafor purposes of this disclosure are not signals per se. Exemplarycomputer storage media include hard disks, flash drives, solid-statememory, phase change random-access memory (PRAM), static random-accessmemory (SRAM), dynamic random-access memory (DRAM), other types ofrandom-access memory (RAM), read-only memory (ROM), electricallyerasable programmable read-only memory (EEPROM), flash memory or othermemory technology, compact disk read-only memory (CD-ROM), digitalversatile disks (DVD) or other optical storage, magnetic cassettes,magnetic tape, magnetic disk storage or other magnetic storage devices,or any other non-transmission medium that can be used to storeinformation for access by a computing device. In contrast, communicationmedia typically embody computer readable instructions, data structures,program modules, or the like in a modulated data signal such as acarrier wave or other transport mechanism and include any informationdelivery media.

Any range or device value given herein can be extended or alteredwithout losing the effect sought, as will be apparent to the skilledperson.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described above.Rather, the specific features and acts described above are disclosed asexample forms of implementing the claims.

It will be understood that the benefits and advantages described abovecan relate to one embodiment or can relate to several embodiments. Theembodiments are not limited to those that solve any or all of the statedproblems or those that have any or all of the stated benefits andadvantages. It will further be understood that reference to ‘an’ itemrefers to one or more of those items.

The examples illustrated and described herein as well as examples notspecifically described herein but within the scope of aspects of theclaims constitute exemplary means for providing a UPS.

The term “comprising” is used in this specification to mean includingthe feature(s) or act(s) followed thereafter, without excluding thepresence of one or more additional features or acts.

In some examples, the operations illustrated in the figures can beimplemented as software instructions encoded on a computer readablemedium, in hardware programmed or designed to perform the operations, orboth. For example, aspects of the disclosure can be implemented as asystem on a chip or other circuitry including a plurality ofinterconnected, electrically conductive elements.

The order of execution or performance of the operations in examples ofthe disclosure illustrated and described herein is not essential, unlessotherwise specified. That is, the operations can be performed in anyorder, unless otherwise specified, and examples of the disclosure caninclude additional or fewer operations than those disclosed herein. Forexample, it is contemplated that executing or performing a particularoperation before, contemporaneously with, or after another operation iswithin the scope of aspects of the disclosure.

When introducing elements of aspects of the disclosure or the examplesthereof, the articles “a,” “an,” “the,” and “said” are intended to meanthat there are one or more of the elements. The terms “comprising,”“including,” and “having” are intended to be inclusive and mean thatthere can be additional elements other than the listed elements. Theterm “exemplary” is intended to mean “an example of” The phrase “one ormore of the following: A, B, and C” means “at least one of A and/or atleast one of B and/or at least one of C.”

Having described aspects of the disclosure in detail, it will beapparent that modifications and variations are possible withoutdeparting from the scope of aspects of the disclosure as defined in theappended claims. As various changes could be made in the aboveconstructions, products, and methods without departing from the scope ofaspects of the disclosure, it is intended that all matter contained inthe above description and shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

What is claimed is:
 1. An uninterruptible power supply (UPS) comprising:a rectifier configured to receive alternating current (AC) power; afirst output connected to the rectifier through an inverter, the firstoutput configured to output an AC power supply; and a second outputconnected to the rectifier through a battery backup and a stepdownconverter, the second output configured to output a direct current (DC)power supply in response to a detected power anomaly condition.
 2. TheUPS of claim 1, wherein the power anomaly condition comprises one of apower failure or an excess power condition.
 3. The UPS of claim 1,wherein the battery backup is connected between the rectifier and theinverter.
 4. The UPS of claim 1, wherein the UPS is coupled within arack and further comprising a power supply unit coupled within the rack,wherein the first output is connected to AC powered equipment in therack and the second output is connected to a DC distribution bus bar,and the DC power supply is sourced to the DC distribution bus bar as acurrent shared power source with an output of the power supply unitduring the power anomaly condition.
 5. The UPS of claim 4, furthercomprising a first power supply line connected to the UPS and a secondpower supply line connected to the power supply unit.
 6. The UPS ofclaim 1, wherein the first output is configured to operate in a highefficiency mode or a double conversion mode.
 7. A dual outputuninterruptible power supply (UPS) comprising: a first output; a secondoutput; an alternating current (AC)/direct current (DC) converterconfigured to convert input AC power to a DC power supplied to a batterybackup; an inverter configured to convert the DC power to AC power tooutput at the first output; and a stepdown converter configured to stepdown the DC power to output at the second output.
 8. The dual output UPSof claim 7, wherein the second output is activated in response to apower anomaly condition.
 9. The dual output UPS of claim 8, wherein thesecond output is in an active state until one or more shut downoperations of connected devices having random-access memory arecompleted.
 10. The dual output UPS of claim 7, wherein the power anomalycondition comprises one of a power failure or excess power condition.11. The dual output UPS of claim 7, wherein the UPS is coupled within arack and further comprising a power supply unit coupled within the rack,wherein the first output is connected to AC powered equipment in therack and the second output is connected to a DC distribution bus bar,and the DC power supply is sourced to the DC distribution bus bar as acurrent shared power source with an output of the power supply unit. 12.The dual output UPS of claim 11, further comprising a first power supplyline connected to the UPS and a second power supply line connected tothe power supply unit.
 13. The dual output UPS of claim 7, wherein thefirst output is configured to operate in modes of operation that aredifferent than modes of operation of the second output.
 14. The dualoutput UPS of claim 7, wherein the first and second output areconfigured for selectable operation in a plurality of operating modescomprising a high efficiency mode of operation, a double conversion modeof operation, a second output backup power mode of operation, and a peakshaving mode of operation.
 15. A method for providing an uninterruptiblepower supply (UPS), the method comprising: configuring a first output ofthe UPS to output an AC power supply from an AC power source; andconfiguring a second output of the UPS to output a DC power supply froman AC power source, the first and second outputs being selectivelyoperable in the UPS and the second output activated during a poweranomaly condition to (i) output power during the power anomaly conditionthat is provided by a power supply unit during normal operation or (ii)power share with a power supply unit.
 16. The method of claim 15,wherein the power anomaly condition comprises one of a power failure orexcess power condition.
 17. The method of claim 15, further comprisingconfiguring the first and second outputs to selectively operate in aplurality of operating modes comprising a high efficiency mode ofoperation, a double conversion mode of operation, a second output backuppower mode of operation, and a peak shaving mode of operation.
 18. Themethod of claim 15, further configuring an alternating current(AC)/direct current (DC) converter to convert the AC power source to aDC power supplied to a battery backup.
 19. The method of claim 15,further comprising configuring a stepdown converter to step down avoltage output of the battery backup.
 20. The method of claim 15,further configuring the first and second outputs for operation at a sametime.